2,2-dimethyl-1,3-dioxolan-4-ylmethanol

Adsorption / desorption

Link to relevant study record(s)

Reference

Endpoint:

adsorption / desorption: screening

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 16 December 2013 to 20 February 2014

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP study performed according international guidelines. No deviation from the guidelines was observed during the test.

Qualifier:

according to guideline

Guideline:

OECD Guideline 121 (Estimation of the Adsorption Coefficient (Koc) on Soil and on Sewage Sludge using High Performance Liquid Chromatography (HPLC))

Deviations:

no

GLP compliance:

yes

Type of method:

HPLC estimation method

Media:

other:

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
PHYSICO-CHEMICAL PROPERTIES
[*) Properties that should be provided for the HPLC method]
- Vapour pressure:
- Water solubility*: 172 mg/ml
- Solubility in organic solvents*:
- Dissociation constant*:2.00
- log Pow*: 0.3
- pKa: 6.52
- Stability of test material at room temperature: test substance stable

OTHER PROPERTIES (if relevant for this endpoint)

Radiolabelling:

no

Details on study design: HPLC method:

EQUIPMENT
- Apparatus:Agilent Series 1100 High Performance Liquid Chromatograph (HPLC)
- Type, material and dimension of analytical column: Agilent Zorbax CN Rapid Resolution HT (50 x 2.1 mm, 1.8 μm particle size)
- Detection system: Refractive Index (RI) Detector

MOBILE PHASES
- Type: Solvent A (45.0%): HPLC-grade Reagent Water
Solvent B (55.0%): Acetonitrile
- Experiments with additives carried out on separate columns: no
- pH: 6.5
- Solutes for dissolving test and reference substances: HPLC Water

DETERMINATION OF DEAD TIME
- Method: by inert substances which are not retained by the column (thiourea 1.0µl of solution at 1.01 mg/ml)

REFERENCE SUBSTANCES
- Identities: Acetanilide, Phenol, Naphthalene, Phenanthrene, DDT
- Solutions reference substances preparation: weighing of references substances in separate vials followed by the addition of 10 ml of 55:45 Acetonitrile:HPLC Water dilution solvent

TEST SUBSTANCE:
- Solution preparation: 0.0102 grams of test substance into vials followed by the addition of 10 ml of 55:45 Acetonitrile:HPLC Water dilution solvent

DETERMINATION OF RETENTION TIMES
- Quantity of test substance introduced in the column: 1.0µL of test substance solution at 1.02ml/ml
- Quantity of reference substances: Acetanilide: 1.0 µl of solution at 1.10 mg/ml, Phenol: 1.0 µl of solution at 1.04 mg/ml, Naphthalene: 1.0 µl of solution at 1.01 mg/ml, Phenanthrene: 1.0 µl of solution at 1.30 mg/ml, DDT: 1.0 µl of solution at 0.56 mg/ml
- Intervals of calibration: prior to and after the test substance

REPETITIONS
- Number of determinations: 2

EVALUATION
- Calculation of capacity factors k': k' = (tR - t0)/t0
- Calculation of retention times: tR= retention time of test substance of reference substances, tO= dead time of the column (established with thiourea)
- Determination of the log Koc value: A correlation graph of log(k') versus log(KOC) for the reference standards was plotted and fitted to a regression equation in the form y = mx + b. Log KOC values for each test substance peak were calculated by substituting the calculated logarithm of the capacity factor for each test substance peak into the linear regression equation for the calibration curve.

Analytical monitoring:

no

Key result

Sample No.:

#1

Type:

other: Log Koc

Value:

<= 1.25 dimensionless

pH:

7

Temp.:

60 °C

Remarks on result:

other: in the HPLC method the percent of organic carbon is not determined

Remarks on result:

other: Not determined

Details on results (HPLC method):

- Retention times of reference substances used for calibration:
Reference materiaI--------- /-tr (min)------/Log k--------/Theoretical Log Koc
Thiourea /1.240
/1.268
Acetanilide /1.406 /0.121 /1.25
/1.424 /0.136
Phenol /1.400 /0.116 /1.32
/1.411 /0.125
Naphthalene /1.630 /0,300 /2.75
/1.706 /0,360
Phenanthrene /1.927 /0,537 /4.09
4,4'DDT /2.744 /1,188 /5.63

The second injections for phenanthrene and DDT were labeled data not reported. An instrumental/injection error occurred during these injections.

- Details of fitted regression line (log k' vs. log Koc): y=0.2276x-1.1771 x=logKoc and Y=log k
R²=0.9804
- Average retention data for test substance: 1.276

Transformation products:

not measured

Injections of a reagent blank solution (55:45 ACN:H2O (v/v)) showed that the reagents used for preparation of the calibration reference standard and test substance solutions were free of any potentially interfering contaminants.

A set of six reference standard solutions were prepared and injected in duplicate (once near the beginning and once near the end of the HPLC sequence). The retention times for one of the reference substances, thiourea, were used to determine the analytical column dead time (t0) for use in calculating capacity factors (k') of the remaining reference substances and the test substance. Five additional reference substances were analyzed. The capacity factors of all the reference substances were calculated based upon their retention times.

The three test substance solutions were sequentially injected. The test substance eluted as one peak. Since the test substance peak eluted prior to the retention time for the lowest calibration reference standard, acetanilide (log KOC = 1.25), the log KOC for the test substance is considered to be < 1.25. The calculated capacity factors and mean adsorption coefficients for the test substance are shown in the table below:

Sample Number (411C-110-)	Capacity factor (k)	Mean k and Standard deviation (SD)	Log k	Koc	Log Koc	Mean log Koc
1	0.0191	0.0173 SD=0.0026	-1.718	<17.8	<1.25	<1.25
2	0.0144		-1.843	<17.8	<1.25
3	0.0183		-1.737	<17.8	<1.25

Validity criteria fulfilled:

yes

Conclusions:

The log Koc of the test substance is <1.25.

Executive summary:

The log Koc of the test substance was performed using the HPLC estimation method according to OECD guideline 122 and GLP. No deviation from the guideline was observed during the study.

In this study, the interaction of the test substance containing polar and/or non-polar functional groups with a dual composition (polar and non-polar sites) HPLC stationary phase mimicked the interaction of the test substance with organic matter present in soil and sludge matrices. The HPLC method is applicable to chemical substances for which an appropriate detection system (e.g. absorbance, refractive index, radioactivity detector, etc.) is available and which do not react either with the eluent or the stationary phase, or interact in a specific way with inorganic components (e.g. formation of cluster complexes with clay minerals).

Capacity factors were calculated for the reference standards using thiourea to estimate column dead time (i.e. the retention time of an unretained organic compound). The logarithms of the capacity factors were then plotted against published log KOC values to establish a linear regression equation.

The test substance peak eluted prior to the retention time for the lowest calibration reference standard, acetanilide (log KOC = 1.25), the log KOC for the test substance is considered to be < 1.25.

Description of key information

Experimental value of Log Koc for the test substance: <1.25

Key value for chemical safety assessment

Koc at 20 °C:

17.78

Additional information

The log Koc of the test substance was performed using the HPLC estimation method according to OECD guideline 122 and GLP. No deviation from the guideline was observed during the study.

The test substance peak eluted prior to the retention time for the lowest calibration reference standard, acetanilide (log KOC = 1.25). So the Log Koc of the test substance is lower than 1.25.